We were recently on a long trip and had an injector go out on our 2003 Silverado Duramax diesel. The truck had 99,325 miles on it. We took it to a Chevy dealer and had them replace all 4 injectors ...
I would add a lubrication additive as your engine (mine also) was not intended to run on ULSD and it will cause premature wear in injectors and pumps. You can run two cycle oil, OPTI-LUBE XPD or FPPF to name a few. FPPF Opti-Lube
